Variable-lift fuel-valve for oil-engines



K. 0. KELLER.

VARIABLE LIFT FUEL VALVE FOR OIL ENGINES.

APPLICATION FILED JAN. 24, 1920.

1,396,935. Patented Nov. 15, 1921.

2 SHEETSSHEET I.

X T J I I g5 W 2 Y 7\ Z 1 6, Merl/tor Mam/M APPLICATION FILED IAN. 24, I920- Patented Nov. 15, 1921,-

2 SHEETS-SHEET 2.

ITIIW III ILL UNITED STATES PATENT OFFICE.

KARL OTTO KELLER, 0F DURHAM, ENGLAND, ASSIGNOR OF ONE-HALF TO ROBERT PILE DOXFORD, OF PALLION YARD, SUNDERLAND, ENGLAND.

VARIABLE-LIFT FUEL-VALVE FOR OIL-ENGINES.

Specification of Letters mam.

Patented Nov. 15, 1921.

Application filed January 24, 1920. SeriaLNo. 353,874.

To all whom it may concern:

Be it known that I, KARL Orro KELLER, a citizen of the Swiss Confederation, residing at Sunderland, Durham, England, have invented certain new and useful Improvements in Variable-Lift Fuel-Valves for Oil-Engines, of which the following is a specification.

This invention relates to variable-lift fuelvalves for oil engines.

It is already known to be desirable in oilengines that a fuel-valve operated by mechanism capable of imparting to it a .given maximum lift should be combined with means for automatically varying as required the height of lift of the valve by limiting it to heights which are less than that of the said maximum, without altering either the duration of the eriod in which the valve is open or the position in the path of the engine crank-pin of the points at which the opening of the-valve commences and the closing finishes. Heretofore when this desired variation of height of lift has been effected' it has been carried out with the aid of linkages more or less complex.

It is the object of the present invention to obviate the use of any complex device for the purpose above described. The present invention therefore is an improvement of an oil-engine provided with a fuel-valve opening apparatus of the usual or other convenient type that causes a valve which admits oil alone or both 'oil and air to be open for a period commencing at an unchanging point in the crank-pin path in successive revolutions of the engine and lastin through a constant angular extent of that path and that is capable of imparting to the valve a given maximum lift, which improvement consists in the combination with said appa- 'ratus of a simple intercepting device which is adjustable by an automatic governor, and is employable to cause the valve, after it has commenced to open at the unchanging point aforesaid and while it remains open through the constant angular extent of crank-pin path, to be intercepted and stoppedin its lifting movement at heights which are less than that of the said maximum lift; this intercepting device truncates' the lift, as will hereinafter appear. i

The invention is hereinafter described with reference to the accompanying drawings in its application to a needle valve which controls the socalled solid injection of a column of fuel oil into the cylinder of an engine. A fuel valve of this kind is described in my prior Patent No. 1,341,911, of June 1, 1920.

In the accompanying drawings,

Figure 1 is a view mainly in vertical central section of a fuel-injection valve which has an adjustable device combined there with according to the present invention;

Fig. 2 is a plan of the parts AL of Fig. 1;

Fig. 3 is a diagram of valve-lift hereinafter more particularly described;

Fig. 4 is a view mainly in vertical central section of a valve-controlling device alternative to that which is shown in Fig. 1, and

Fig. 5 is a plan of Fig. 4 on the line 5--5, Fig. 4.

Like letters of reference indicate like parts throughout the drawings.

With reference first to Figs. 1 and 2:

The upper part or pilot ram of the valve is numbered 1 and the needle-valve proper or lower part of the valve by which part the issuance of theoil at O is cont-rolled is numthe parts 1, 2, 3, z. 6., normal to the line in which all three parts reciprocate.

In the cylindrical guide G the part 1 has a fluid-tight sliding fit and its top end serves as a piston therein. On its top end bears a light spring LS kept in place by the screw S and gas-tight plug P.

In the cylindrical guide G which is alined with the guide G the needle-valve proper, 3, is a fluid-tight sliding fit; it serves as a piston therein, and from its lower end its tapered tip extends into the fuelopening 0 leading into the engine-cylinder.

A pipe BC which is the pressure-equalizing conduit maintains constant communication between the top end of the upper cylinder G" and the bottom interior of the lower cylinder G It communicates with the latter by making a 'unction at J with the fuelinlet conduit F 1 leading from the source of oil. under pressure. D is a drain.

The lower end of the upper cylinder G and the upper end of the lower cylinder G serve respectively as guides for the upper and lower ends of the pusher-rod 2, which extend into them as shown.

The rocker-lever RL gives an upward movement to the pusherrod 2 and the pusher-rod is followed in this upward movement by the part 3 by reason of the upward pressure of oil on the lower end of the latter. The part 3 can thus follow the upward movement of 2 throughout a vertical movement suflicient to give a predetermined maximum lift to the part 3.

- The exterior of the cylindrical guide G which is stationary, is externally screwthreaded with a quick thread T. On this threaded portion turns a nut N which is an intercepting device such as is hereinbefore referred to and through the center of which the upper end of the part 3 can rise and fall. Fixed on the part 3 is a collar K which will abut against the under. face F of the top part of this nut N in the circumstances hereinafter ex lained.

To the nut is fixed an arm A which can be connected by a link L to an automatic of 3; but if it be automatically or otherwise screwed along the thread T it can be moved .to and held at a level at which its under ment to occur at the usual place and time.

For example, take Fig. 3. In this figure the curve V W X Y Z is a graph of the gradual opening and closing movement of a part such as 3 aforesaid over a period whose durationis indicated in extent of angular movementof the engine crank-pin in its circular path by the length of the horizontal line V H Z. Vertical movement of the valve in lift is measured vertically from the strai ht horizontal V H Z to the curve V W X Z. This movement beginning at V and ending at Z is shown by the curve V V X Y Z under conditions in which the valve is receiving maximum lift. When the lift is limited by the interception of the valve in its upward path the movement of the valve is exactly as before except that the curve becomes V W 2 Y Z; the motion of the valve begins and ends gradually, as before,

and at the same places as before, but the lift is less.

However much the lift may be truncated, in the manner hereinbefore described, the gradual character of the initial opening and the final closing movement of the valve remains unaltered, for it will be seen from Fig. 3 that it is only the middle portion of the motion curve that is altered, and that this becomes a straight line.

In the alternative construction illustrated in Figs. 4 andv 5, the needle-valve proper, numbered 3, terminates at its upper end in a flat-disk 3 which abuts against, but is not connected with, the lower end of the pusher-rod 2, which latter is operated as in the preceding example. To a stationary pivot SP are pivoted twin levers TL; each lever is connected to its companion by a boss B through the center of which the part 2 can rise and fall. On the under-side of this boss are intercepting projections N against which the disk 3 will abut when it rises. These projections, if the twin levers TL be turned upward sufficiently far about the stationary pivot SP will have no effect on the lift of 3; but if the twin levers be automatically moved downwardly from the extreme 'upward limit of their movement, the projections can thereby be moved to and held at a level at which their under-faces will intercept the disk 3 in the upward movement of the part 3 and will .thus prevent the maximum lift of the latter from occurring, truncating the lift as in the previous example. Thus the projections N stop the opening movement of the part 3 after that movement has commenced, which it will do at the usual place and time, and allow the return movement of the part 3 to occur, likewise at the usual place and time. To adjust the level of the projections N automatically, an eccentric E is provided fixed upon a shaft E rotatably mounted in a fixed bearing FB in the casting C. Against this eccentric a roller R pivoted in the free end of the twin levers TL is held by a spring sp, the lower end of which engages the lever, and the upper end of which is secured to a bracket B on the casting C, as shown When the shaft E is rotated automatically the eccentric E will push the twin levers down or allow them to rise, and the projections N will be altered in level accordingly.

What I claim as my invention and desire to secure by Letters atent is 1. In an oil engine, a fuel valve having a maximum opening movement, means capable of causing said valve to open to said maximum extent, said means being initially and finally effective at unchanging points in the crank-pin path in successive revolutions of the engine for producing intervals lasting through an unchanging angular extent of said path between the opening and maximum extent, said means being initially and finally effective at unchanging points in the crank-pin path in successive revolutions of the engine for producing intervals lasting through an unchanging angular extent between the opening and closing of the valve, and adjustable means for limiting the extent of opening movement thereof, means comprising twin levers cooperating with said valve, and an eccentric for changlng the position of said levers, substantially as described.

3. In an oil engine, a fuel valve, fuel -pressure connections leading thereto for subjecting said valve to pressure tending to open the same a predetermined maximum dlstance, means for holding said valve closed against said fluid pressure, means initially and finally efiective at unchanging points in successive cycles of operation of the engine for rendering said holding means.

inoperative to permit opening of the valve, and means for variably limiting the extent of opening of the valve, said means comprising twin' levers cooperating with said valve, and an eccentric for changing the position of said levers, substantially as described.

4. In an oil engine, a valve, means for feeding fuel thereto under pressure, means for causing the said valve to open and close at unchanging points in successive cycles of operation of the engine whereby intervals lasting through an unchanging angular extent are produced between the o ening and closing of the valve and means or varying the extent of opening of the valve irrespective of the pressure of the fuel, said means comprising twin levers cooperating with said valve, and an eccentric for changing the position of said levers, substantially as described.

5. In an oil engine, the combination of a fuel valve having a maximum opening movement, and having a divided stem whereof one part is provided with the valve proper and a second part is movable independently thereof away from and toward the same, means tending to cause the two parts of the valve-stem to move together in unison, valve-actuating means operatively connected with said second part of the valve-stem and capable of causing the valve to open to said maximum extent, said valveaetuating means being initially and finally effective at unchanging points in the crankpin path in successive revolutions of the engine for producing intervals lasting through an unchan ing angular extent of said path between t e opening and closing of the valve, and intercepting means arranged to coact with the said part of the valve-stem rovided with the valve proper for variably imiting the extent of o ening movement thereof, substantially as described.

6. In an oil engine, the combination of a fuel valve having a maximum opening movement, and having a divided stem whereof one part is provided with the valve proper and a second part is movable independently thereof away from and toward the stem, means tending to cause the two parts of the valve stem to move together in unison, valve-actuating means operatively connected with said second part of the valve stem and capable of causing the valve to open to said maximum extent, said valve actuating means being initially and finally effective at unchanging points in the crankpin path in successive revolutions of the engine for producing intervals lasting through an unchanging angular extent of said path between the opening and closing of the valve, and adjustable intercepting means arranged to coact with the said partof the valve stem provided with the valve proper for variably limiting the extent of opening movement thereof, substantially as described;

7. In an oil engine, the combination of a fuel valve having a maximum opening movement, and having a divided stem whereof one part is provided with the valve proper and a second part is movable independently thereof away from and toward the same, fuel-pressure connections leading to the two parts of the valve stem for subjectlng the same to pressure tending to cause its two parts to move together in unison, valve-actuating means operatively connected with said second part of the valve stem and capable of causing the valve to open to said maximum extent, said valveactuating means being initially and finally effective at unchanging points in the crankp n path in successive revolutions of'the engine for producing intervals lasting through an unchanglng angular extent of said path between the opening and closing of the valve, and intercepting means arranged to coact with the said part of the valve stem provided with the valve proper for variably the same, means tending to cause the two parts of the valve stem to move together in unison, valve-actuating means operatively connected with said second part of the valve stem and capable of causing the valve to open to said maximum extent, said valveactuating means being initially and finally effective at unchanging points in the crank pin path in successive revolutions of the engine for producing intervals lasting through an unchanging angular extent of said path between the opening and closing of the valve, and intercepting means comprising a lever arranged to cooperate with the first part of the valve stem, and means for changing the position of said lever, substantially as described.

9. In an oil engine, the combination of a fuel valve having a maximum opening movement and having a divided stem whereof one part is provided with the valve proper and a second part is movable independently thereof away from and toward the same, means tendingto cause the two parts of the valve stem to move together in unison, valve-actuating means operatively connected with said second part of thevalve stem and capable of causing the valve to open to said maximum extent, said valveactuating means beinginitially and finally effective at unchanging points in the crankpin path in successive revolutions of the engine for producing intervals lastin through an unchanging angular extent'o said path between the opening and closing of the valve, and intercepting means comprising twin levers arranged to cooperate with the first part of the valve-stem, and an eccentric for changing the position of said levers, substantially as described.

In testimony whereof I affix my signature.

KARL OTTO KELLER. 

